1. Technical Field
The present disclosure pertains to semiconductor and integrated circuit devices, including micro-fabricated structures such as Micro-Electromechanical Systems (MEMS) and Nano-Electromechanical Systems (NEMS) such as BioMEMS, RFMEMS, OPTO-MEMS, etc.
2. Description of the Related Art
Electronic circuits, which are fabricated on semiconductor substrates, perform a variety of functions. Some examples are electronic circuits formed as amplifiers, filters, MEMS device, power supplies, etc. In some cases, many circuits are formed on a single semiconductor substrate to provide a multitude of functions. The end product of the fabrication is commonly called a semiconductor “chip” or integrated circuit.
The electronic circuits are often constructed on a semiconductor substrate. The substrate may initially be a single wafer, and after several electronic circuits are formed, the wafer is cut into many individual semiconductor chips. Later, each chip may be packaged in its own plastic or other suitable housing for use in an electronic system.
In order to maximize return on investment, manufacturers of semiconductor chips try to maximize the number of operational chips that can be formed on a single wafer. The number of operational chips that can be formed on the wafer may be affected by several factors. Using current technology, the semiconductor wafer may have a diameter of 6 inches, 8 inches, 12 inches or some other suitable size. In addition to the diameter of the wafer, the number of individual chips that can be formed from a single wafer may be limited by the type, size, complexity, and function of the electronic circuits that are fabricated.
Current integrated circuit and semiconductor device trends focus on obtaining higher integration levels through smaller feature sizes. For example, following what is referred to as Moore's law, it is often presumed that due to miniaturization, the number of transistors that can be practically placed on an area of, for example, a wafer, doubles approximately every two years. While planning and design of devices based on the assumptions of Moore's law has some advantages and Moore's law has, at least for the past few decades, proven to be reliable, reduction of the size of the dimensions of components, such as transistors, often requires new equipment. The processing of wafers to produce integrated circuit chips occurs in a number of different steps. The steps are often carried out in different etch chambers, others are carried out in furnaces, while others of which are deposition or implantation chambers. Capital costs of several tens of million dollars each are not unusual for these types of equipment, such as wafer-processing equipment, chambers, etc.